Ramblings on our journeys exploring and questioning the validity of "established" scientific "fact."

Tuesday, January 13, 2009

USDA Food Pyramid Update

The USDA will be updating its food pyramid again next year. At present there is little or no representation from the low-carb community on the panel charged with creating the update. Dr. Michael Eades is soliciting comments to be passed on to the panel on his Protein Power blog. If you are interested in contributing, go to his website and provide a comment. I have reproduced below a comment that I posted there.

Let’s see… populations that have found low-carb diets to have significant health and performance benefits: overweight and obese, diabetic, epileptic, persons at high risk for heart disease, models, actors, endurance athletes (have I missed any?); populations that have problems with low-carb diets: none (unless maybe you count those whose problems are in the form of poor acceptance by family, friends, and coworkers…) But it’s “unproven,” isn’t it? Well, we’d all like to see more extensive data on larger populations. But surely, the obvious failure of current dietary recommendations which HAVE been tested extensively and shown to be seriously flawed, suggests that we need a new approach. Low-carb diets which have shown such clear benefits for so many populations are so clearly superior to the current food pyramid, that we are due for some class-action lawsuits (against the USDA, individual panelists, other medical societies, food industry lobbyists, pharmaceutical companies?) for so blatantly putting self-interests above public health!

My personal story: mid-50s, low-carb for one year after a lifetime of high-carb diets. Used to tolerate high-carb diet well and be able to eat large meals without gaining weight. Weight crept up over time, then started rising faster. Gradual appearance of symptoms of metabolic syndrome (fasting glucose up, blood pressure up, weight up, etc.) Low-carb diet rapidly reversed problems: lost 30 pounds without calorie restriction, blood pressure and fasting glucose down, improved general health and athletic performance (I took up running ultramarathons and now do so on little or no carbohydrates and feel good during and after the events [and I now comfortably run hilly distances of up to about 20 miles/4 hours on no supplemental food at all]). And no, the high level of exercise did not result in my weight loss and health improvement; rather the health improvement and weight loss ENABLED me to increase my level of exercise. If anything, the weight loss has plateaued and reversed slightly with increasing exercise.

It is clear that there are populations that can tolerate and even thrive on high-carbohydrate diets for a lifetime. But my best estimates from data I’ve seen is that these are a minority—probably well under 20% of the general population, and they probably represent predominantly people with either limited access to food and/or people with a high level of daily physical activity.

My recommended changes to general dietary guidelines: start with a baseline of about 20% carbs, 65% fat, 15% protein. Increase carbs only if weight GAIN is needed. Decrease carbs further for weight loss or other specific health conditions such as diabetes. Increase protein if needed for muscle building/repair (athletes). For most people, this sort of diet is best achieved with a lot of meat, fish, nuts, and vegetables, though details can vary widely depending on availability and any religious, cultural, or specific health/allergy issues. Sugars and simple starches should be used sparingly if at all. These include nutritive sweeteners, most wheat, rice, corn, and other grain products. Fruits should also be limited: most are nutritionally predominantly sugar water. Dairy is more controversial. Personally, I do not limit dairy consumption, although some people find it desirable to limit or cut dairy entirely. Legumes and legume products (such as soy products) should probably be consumed in moderation, and may be left out by personal preference. Within these general guidelines, try to eat a wide variety of food.

I think it is most important to focus first and foremost on getting these macronutrient guidelines established and understood. Micronutrients are clearly also important, and since fat is to be recommended as the major source of calories, it is probably also important to recommend emphasizing or avoiding particular types of fat, but these kinds of recommendations should be given a secondary status to the macronutrient recommendations. The “wide variety of food” recommendation should take care of most micronutrient needs for most people.

You might like the "Palo Diet for Athletes" by Loren Cordain and Joel Friel. They basically tell you to carb up before (but watch out for insulin spike) and after workouts and eat paleo the rest of the time. That seems to be the nutrition advice of the Crossfit people and the endurancecorner.com coaches too. I think the question is what kind of carbs, how much and when. David is using very little carbs, but he usually isn't training anywhere near his lactate threshold, whereas I push into mine pretty often trying not to hold him back too much. I can say that we've had very few illnesses and injuries since we went low carb (except for the muscle strains i get now and then- usually piriformis related i think), and I think that could be partly due to the diet (lots of vitamins and protein). I assume you are experimenting yourself- let us know what works for you!

Great post...I was the weak one inthat group of scientists at the ZR Opening...not being a scientist per se....I would like to correspond and collaborate with you.I am working on some info on optimized fat metabolism and its all working well. you can reach me at peter@vespapower.com

About Us

Two scientists (doctorates in Biophysical Chemistry and Gas Dynamics, respectively), married (to each other) and currently practicing patent law (as patent attorney and agent respectively). Wide-ranging knowledge and interests; continuing to discover that at least half of what they learned in school is wrong.